I'm a (stubborn) 60-year old woman and put this up myself.  It took a great deal of goofing around with the panels and track system (taking things apart) to figure out how to make it open from left to right, but eventually I got it.  I mounted it extended to the full extent, so it extends a few inches wider than my sliding door on the left, so when it's open, it only blocks part of one door and preserves some light.  Now that it's up, I really love it.  But their claim that it easily opens either way is misleading.